7.2 Flashcards
what happens durring inhalation
intercostal muscles contract, diaphram contracts down causing the thoraic cavity volume to increase, decreasing pressure and air moves into lungs
what happens during exhalation
intercoastal muslces relax, diaphram relaxes, thoraic cavity volume decreases causing pressure to increase leading lungs to exhale.
spirograph?
represents the amount of air that moves into and out of the lungs with each breath.
Tidal volume?
is the volume of air that
is inhaled and exhaled in a normal
breathing movement when the body
is at rest.
Inspiratory reserve volume?
is the additional volume of air that can be taken into the lungs, beyond a regular
Expiratory reserve volume?
the additional volume of air that can be forced out of the lungs, beyond a
regular
Vital capacity?
the total volume of gas
that can be moved into or out of the
lungs. It can be calculated as tidal
volume + inspiratory reserve
Residual volume?
the amount of gas that remains in the lungs and the passageways of the respiratory system even after a full exhalation. This gas never leaves the respiratory system if it did, the lungs and respiratory passageways would collapse. The residual volume has little value for gas exchange because it is not exchanged with air from the external environment.
respiration has 2 seperate processes, what are they
external and internal
external respiration?
takes place in the lungs. gases are
exchanged between the alveoli and the blood in the capillaries. oxygen
diffuses out of the alveoli into the blood in the capillaries.
what’s the difference between diffusion and facilitated diffusion
protein-based molecules in the wall of the alveoli facilitate diffusion by “carrying” oxygen across the cell membranes. This process
does not require extra energy
why does The air that enters the
alveoli after inhalation has a higher
concentration of oxygen than the blood in the capillaries next to the lungs.
The blood in the capillaries has had oxygen diffuse out of it into the tissue cells and has had carbon dioxide diffuse into it from the tissue cells.
The blood in the capillaries has a
higher concentration of carbon dioxide than the alveoli because?
it is returning from the body tissues from cell rep. Thus, the carbon dioxide diffuses into the alveoli from the capillaries. The carbon dioxide is then exhaled into the air.
Once oxygen and carbon dioxide have been exchanged between the capillaries and alveoli, what happens next?
the blood in the capillaries
begins its journey back to the heart and then on to the tissue cells. There, it undergoes internal respiration and
exchanges the oxygen for carbon dioxide once again.
Approximately 99 percent of the oxygen that reaches cells is carried by an oxygen-transporting molecule called?
hemoglobin, which is only in red blood cells.
where is c02 dissolved?
70 percent is dissolved
and carried in the blood as bicarbonate ion (HCO3-).
how is Carbonic acid (H2CO3)
is formed in the blood?
carbon dioxide reacts with a water molecule. The carbonic acid quickly breaks down into a hydrogen ion (H+) and a bicarbonate ion. This reaction occurs in the red blood cells. The H+ then combines with hemoglobin, and the bicarbonate ions diffuse out of the red blood cells into the plasma, which is carried to the lungs.
